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https://www.readbyqxmd.com/read/28645203/neurosurgical-randomized-controlled-trials-distance-travelled
#1
Tej D Azad, Anand Veeravagu, Vaishali Mittal, Rogelio Esparza, Eli Johnson, John P A Ioannidis, Gerald A Grant
BACKGROUND: The evidence base for many neurosurgical procedures has been limited. We performed a comprehensive and systematic analysis of study design, quality of reporting, and trial results of neurosurgical randomized controlled trials (RCTs). OBJECTIVE: To systematically assess the design and quality characteristics of neurosurgical RCTs. METHODS: From January 1961 to June 2016, RCTs with >5 patients assessing any 1 neurosurgical procedure against another procedure, nonsurgical treatment, or no treatment were retrieved from MEDLINE, Scopus, and Cochrane Library...
June 21, 2017: Neurosurgery
https://www.readbyqxmd.com/read/28645036/influence-of-surface-states-on-blinking-characteristics-of-single-colloidal-cdse-cds-zns-core-multishell-quantum-dot
#2
Hao Xu, Hjalmar Brismar, Ying Fu
We carefully characterized the fluorescence blinking of single colloidal CdSe-CdS/ZnS core-multishell quantum dots (QDs) with different surface modifications, including octadecylamine (ODA) coated QDs dispersed in chloroform, aqueous 3-mercaptopropionic acids (3MPA) coated QDs in HEPES solution treated by Ca(2+) ions and ethylene glycol tetraacetic acid (EGTA, Ca(2+) chelator), and aqueous 3MPA-QDs treated by glycerol. It was found that the on- and off-state probability density distributions displayed different rules...
June 16, 2017: Journal of Colloid and Interface Science
https://www.readbyqxmd.com/read/28644850/visceral-adiposity-index-predicts-the-conversion-of-metabolically-healthy-obesity-to-an-unhealthy-phenotype
#3
Yu Mi Kang, Chang Hee Jung, Yun Kyung Cho, Jung Eun Jang, Jenie Yoonoo Hwang, Eun Hee Kim, Woo Je Lee, Joong-Yeol Park, Hong-Kyu Kim
OBJECTIVE: Some individuals with metabolically healthy obesity (MHO) convert to metabolically unhealthy obesity (MUO) phenotype, and visceral adiposity is one of proposed mechanisms underlying such conversion. Visceral adipose index (VAI) is a novel mathematical model which estimates visceral adiposity based on anthropometric and lipid profiles. We aimed to determine the association of VAI-estimated visceral adiposity with the MHO-to-MUO conversion and the predictive value of VAI in estimating such unfavorable outcomes...
2017: PloS One
https://www.readbyqxmd.com/read/28644820/investigation-of-real-tissue-water-equivalent-path-lengths-using-an-efficient-dose-extinction-method
#4
Rongxiao Zhang, Esther Baer, Kyung-Wook Jee, Gregory C Sharp, Jay Flanz, Hsiao-Ming Lu
For proton therapy, an accurate conversion of CT HU to relative stopping power (RSP) is essential. Validation of the conversion based on real tissue samples is more direct than the current practice solely based on tissue substitutes and can potentially address variations over the population. Based on a novel dose extinction method, we measured water equivalent path lengths (WEPL) on animal tissue samples to evaluate the accuracy of CT HU to RSP conversion and potential variations over a population. A broad proton beam delivered a spread out Bragg peak to the samples sandwiched between a water tank and a 2D ion-chamber detector...
June 23, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28644017/spectrally-undiscerned-isomers-might-lead-to-erroneous-determination-of-water-exchange-rates-of-paracest-eu-iii-agents
#5
Nevenka Cakić, Ben Tickner, Moritz Zaiss, David Esteban-Gómez, Carlos Platas-Iglesias, Goran Angelovski
We report a detailed study of the solution structure and water exchange rate of a Eu(III) complex with the cyclen-based ligand L(1), containing (S)-2-(2-acetamido)-3-(4-(trifluoromethyl)phenyl)propanoate pendant arms at positions 1 and 7 of the cyclen ring and acetylglycinate pendants at positions 4 and 10. The EuL(1) complex was characterized by a combination of NMR and luminescence spectroscopy and density functional theory (DFT) calculations. The chemical exchange saturation transfer (CEST) spectra obtained at different temperatures and saturation powers present a CEST signal attributed to the coordinated water molecule...
June 23, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28643387/non-gaussian-diffusion-imaging-with-a-fractional-order-calculus-model-to-predict-response-of-gastrointestinal-stromal-tumor-to-second-line-sunitinib-therapy
#6
Lei Tang, Yi Sui, Zheng Zhong, Frederick C Damen, Jian Li, Lin Shen, Yingshi Sun, Xiaohong Joe Zhou
PURPOSE: To demonstrate the clinical value of a non-Gaussian diffusion model using fractional order calculus (FROC) for early prediction of the response of gastrointestinal stromal tumor to second-line sunitinib targeted therapy. METHODS: Fifteen patients underwent sunitinib treatment after imatinib resistance. Diffusion-weighted imaging with multiple b-values was performed before treatment (baseline) and 2 weeks (for early prediction of response) after initiating sunitinib treatment...
June 22, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28643030/hospital-electronic-prescribing-system-implementation-impact-on-discharge-information-communication-and-prescribing-errors-a-before-and-after-study
#7
Pamela Ruth Mills, Anita Elaine Weidmann, Derek Stewart
PURPOSE: The study aimed to test the hypothesis that hospital electronic prescribing and medicine administration system (HEPMA) implementation impacted patient discharge letter quality, nature and frequency of prescribing errors. METHOD: A quasi experimental before and after retrospective case note review was conducted in one United Kingdom district general hospital. The total sample size was 318 (random samples of 159 before and after implementation), calculated to achieve a 10% error reduction with a power of 80% and p < 0...
June 22, 2017: European Journal of Clinical Pharmacology
https://www.readbyqxmd.com/read/28642711/weekly-time-course-of-neuro-muscular-adaptation-to-intensive-strength-training
#8
Niklas Brown, Dieter Bubeck, Daniel F B Haeufle, Johannes Weickenmeier, Ellen Kuhl, Wilfried Alt, Syn Schmitt
Detailed description of the time course of muscular adaptation is rarely found in literature. Thus, models of muscular adaptation are difficult to validate since no detailed data of adaptation are available. In this article, as an initial step toward a detailed description and analysis of muscular adaptation, we provide a case report of 8 weeks of intense strength training with two active, male participants. Muscular adaptations were analyzed on a morphological level with MRI scans of the right quadriceps muscle and the calculation of muscle volume, on a voluntary strength level by isometric voluntary contractions with doublet stimulation (interpolated twitch technique) and on a non-voluntary level by resting twitch torques...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/28642703/different-regulation-of-interleukin-1-production-and-activity-in-monocytes-and-macrophages-innate-memory-as-an-endogenous-mechanism-of-il-1-inhibition
#9
Mariusz P Madej, Elfi Töpfer, Diana Boraschi, Paola Italiani
Production and activity of interleukin (IL)-1β are kept under strict control in our body, because of its powerful inflammation-promoting capacity. Control of IL-1β production and activity allows IL-1 to exert its defensive activities without causing extensive tissue damage. Monocytes are the major producers of IL-1β during inflammation, but they are also able to produce significant amounts of IL-1 inhibitors such as IL-1Ra and the soluble form of the decoy receptor IL-1R2, in an auto-regulatory feedback loop...
2017: Frontiers in Pharmacology
https://www.readbyqxmd.com/read/28642271/powerful-genetic-association-analysis-for-common-or-rare-variants-with-high-dimensional-structured-traits
#10
Xiang Zhan, Ni Zhao, Anna Plantinga, Timothy A Thornton, Karen N Conneely, Michael P Epstein, Michael C Wu
Many genetic association studies collect a wide range of complex traits. As these traits may be correlated and share a common genetic mechanism, joint analysis can be statistically more powerful and biologically more meaningful. However, most existing tests for multiple traits cannot be used for high-dimensional and possibly structured traits, such as network-structured transcriptomic pathway expressions. To overcome potential limitations, in this paper we propose the dual kernel-based association test (DKAT) for testing the association between multiple traits and multiple genetic variants, both common and rare...
June 22, 2017: Genetics
https://www.readbyqxmd.com/read/28641555/supervised-machine-learning-methods-applied-to-predict-ligand-binding-affinity
#11
Gabriela Sehnem Heck, Val Oliveira Pintro, Richard Rene Pereira, Mauricio Boff de Ávila, Nayara Maria Bernhardt Levin, Walter Filgueira de Azevedo
BACKGROUND: Calculation of ligand-binding affinity is an open problem in computational medicinal chemistry. The ability to computationally predict affinities has a beneficial impact in the early stages of drug development, since it allows a mathematical model to assess protein-ligand interactions. Due to the availability of structural and binding information, machine learning methods have been applied to generate scoring functions with good predictive power. OBJECTIVE: Our goal here is to review recent developments in the application of machine learning methods to predict ligand- binding affinity...
June 22, 2017: Current Medicinal Chemistry
https://www.readbyqxmd.com/read/28641435/validating-and-implementing-modified-filinov-phase-filtration-in-semiclassical-dynamics
#12
Matthew S Church, Sergey V Antipov, Nandini Ananth
The Mixed Quantum-Classical Initial Value Representation (MQC-IVR) is a recently introduced approximate semiclassical (SC) method for the calculation of real-time quantum correlation functions. MQC-IVR employs a modified Filinov filtration (MFF) scheme to control the overall phase of the SC integrand, extending the applicability of SC methods to complex systems while retaining their ability to accurately describe quantum coherence effects. Here, we address questions regarding the effectiveness of the MFF scheme in combination with SC dynamics...
June 21, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28640758/consecutive-ultra-short-term-heart-rate-variability-to-track-dynamic-changes-in-autonomic-nervous-system-during-and-after-exercise
#13
Xiang Chen, Ruijie Yao, Gezhen Yin, Jin Li
OBJECTIVE: Quantitative measurement of the dynamic changes in autonomic nervous system (ANS) during and after exercise has great significance in clinical, sports training and other fields. A consecutive ultra-short-term (30 s, UST) heart rate variability (HRV) method was proposed to track the exercise-induced autonomic control of heart rate (HR). APPROACH: Twenty-three healthy young men participated in the study. The first four stages of the Modified Bruce Protocol (S0-S3) were performed...
June 22, 2017: Physiological Measurement
https://www.readbyqxmd.com/read/28640634/structure-prediction-for-surface-induced-phases-of-organic-monolayers-overcoming-the-combinatorial-bottleneck
#14
Veronika Obersteiner, Michael Scherbela, Lukas Hörmann, Daniel Wegner, Oliver T Hofmann
Structure determination and prediction pose a major challenge to computational material science, demanding efficient global structure search techniques tailored to identify promising and relevant candidates. A major bottleneck is the fact that, due to the many combinatorial possibilities, there are too many possible geometries to be sampled exhaustively. Here, an innovative computational approach to overcome this problem is presented, that explores the potential energy landscape of commensurate organic/inorganic interfaces where the orientation and conformation of the molecules in the tightly packed layer is close to a favorable geometry adopted by isolated molecules on the surface...
June 22, 2017: Nano Letters
https://www.readbyqxmd.com/read/28639831/diagnostic-performance-and-confidence-of-contrast-enhanced-ultrasound-in-the-differential-diagnosis-of-cystic-and-cysticlike-liver-lesions
#15
Antonio Corvino, Orlando Catalano, Fabio Corvino, Fabio Sandomenico, Antonella Petrillo
OBJECTIVE: The aims of this study were to assess the diagnostic performance of contrast-enhanced ultrasound (CEUS) in the characterization of atypical cystic and cysticlike focal liver lesions in comparison with conventional US and to determine whether the use of CEUS can reduce the need for further diagnostic workup. SUBJECTS AND METHODS: In a 3-year period 48 patients with 50 atypical cystic and cysticlike lesions found at conventional US underwent CEUS. Diagnostic confirmation was obtained in cytohistopathologic examinations, with other imaging modalities, and in follow-up...
June 22, 2017: AJR. American Journal of Roentgenology
https://www.readbyqxmd.com/read/28639168/sensitivity-of-chaos-measures-in-detecting-stress-in-the-focusing-control-mechanism-of-the-short-sighted-eye
#16
Karen M Hampson, Matthew P Cufflin, Edward A H Mallen
When fixating on a stationary object, the power of the eye's lens fluctuates. Studies have suggested that changes in these so-called microfluctuations in accommodation may be a factor in the onset and progression of short-sightedness. Like many physiological signals, the fluctuations in the power of the lens exhibit chaotic behaviour. A breakdown or reduction in chaos in physiological systems indicates stress to the system or pathology. The purpose of this study was to determine whether the chaos in fluctuations of the power of the lens changes with refractive error, i...
June 21, 2017: Bulletin of Mathematical Biology
https://www.readbyqxmd.com/read/28638684/the-new-acr-eular-criteria-for-rheumatoid-arthritis-can-identify-patients-with-same-disease-activity-but-less-damage-by-ultrasound
#17
Sibel Zehra Aydın, Concepcion Castillo-Gallego, Jackie Nam, Jane Freeston, Sarah Horton, Richard J Wakefield, Paul Emery
OBJECTIVE: We aimed to compare the ultrasound findings of patients fulfilling the 1987 ACR [OLD-rheumatoid arthritis (RA)] and the new ACR/EULAR (NEW-RA) classification criteria to examine the impact of the new criteria on disease characteristics, particularly disease duration. MATERIAL AND METHODS: A total of 2730 hands, wrists, elbows, knees, ankles, and foot joints of 105 consecutive patients with inflammatory arthritis, i.e., 82 patients fulfilling the RA criteria (60 patients, OLD-RA; 22 patients, NEW-RA alone) and 23 patients with undifferentiated arthritis, were scanned using ultrasound...
June 2017: European Journal of Rheumatology
https://www.readbyqxmd.com/read/28638605/effect-of-ethnicity-and-socioeconomic-status-on-vascular-access-provision-and-performance-in-an-urban-nhs-hospital
#18
Teun Wilmink, Anika Wijewardane, Kathryn Lee, Alexander Murley, Lee Hollingworth, Sarah Powers, Jyoti Baharani
BACKGROUND: The aim of this study was to examine the effect of ethnicity, socioeconomic group (SEG) and comorbidities on provision of vascular access for haemodialysis (HD). METHODS: This was a retrospective review of two databases of HD sessions and access operations from 2003-11. Access modality of first HD session and details of transplanted patients were derived from the renal database. Follow-up was until 1 January 2015. Primary failure (PF) was defined as an arteriovenous fistula (AVF) used for fewer than six consecutive dialysis sessions...
February 2017: Clinical Kidney Journal
https://www.readbyqxmd.com/read/28637401/relationship-between-ambulatory-arterial-stiffness-index-aasi-and-night-day-blood-pressure-ratio-in-essential-hypertensives
#19
Domenico Di Raimondo, Alessandra Casuccio, Rosangela Di Liberti, Gaia Musiari, Valentina Zappulla, Alessandra D'angelo, Antonio Pinto
BACKGROUND: Ambulatory Arterial Stiffness Index (AASI) has been proposed as an indirect and simpler method to estimate the Arterial Stiffness (AS). AASI, calculated from a set of data collected during a 24-hours ambulatory blood pressure monitoring (ABPM), is defined as 1 minus the regression slope of diastolic on systolic blood pressure (BP) values. For a given increase in diastolic BP, the increase in systolic BP is smaller in a compliant compared to a stiff artery; the stiffer the arterial tree, the closer AASI is to 1...
June 21, 2017: Current Hypertension Reviews
https://www.readbyqxmd.com/read/28636314/giant-thermal-rectification-from-single-carbon-nanotube-graphene-junction
#20
Xueming Yang, Dapeng Yu, Bingyang Cao
We describe the influence of the geometry parameters on the thermal rectification of single carbon nanotube-graphene junction. The two-dimensional (2D) distribution of the thermal rectification with respect to the tube length and the side length of the graphene nanosheet are calculated and visualized. The maximum thermal rectification ratios of the designed single carbon nanotube-graphene junction can reach 1244.1% and 1681.6% at average temperatures of 300 K and 200 K, respectively. These values are much higher than those reported for single-material nanostructure-based thermal rectifiers...
June 21, 2017: ACS Applied Materials & Interfaces
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